Direct-drive coiler

ABSTRACT

For a directly driven coiler for winding rolled strip into coils, a piston/cylinder unit is proposed which can be supplied with pressure medium through rotary feeds arranged on a shaft extension or on a coiler shaft.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a directly driven coiler for winding rolledstrip into coils in accordance with the preamble of claim 1.

2. Description of the Related Art

Such directly driven coilers have become known, for example, throughDE-PS 17 52 185 or DE-OS 39 39 119. In these coilers, the relative axialdisplacement between the coiler shaft and the plunger connected to thesegments is effected through mechanical adjustment drives. Theseadjustment drives are bent lever drives or spring assemblies and spacerelements which can only be actuated when the coiler stands still. Anyretightening during the coiling process is not possible in theseadjustment drives.

Piston-cylinder units have become known through DE-OS 35 02 452 by meansof which it is possible to tighten and release the spring assemblieswhich serve as adjustment drives and have the above-describeddisadvantages.

EP-PS 0 004 854 also discloses a piston-cylinder unit which servesdirectly as an adjustment drive for spreading and despreading thecoiler. However, these two coilers provided with piston/cylinder unitsare not directly driven coilers of the generic type mentioned above, butindirectly driven coilers in which the drive motor is arranged next tothe coiler shaft.

The coiler according to EP-OS 0 004 854 does have central rotary feeds,so that, for example, retightening during the coiling procedure ispossible, however, if the drive motor for the coiler were to be flangeddirectly to the coiler shaft, this would result in difficulties inconnection with the pressure medium supply because, as a rule, onlysolid motor shafts are being used, so that the pressure medium could notbe conducted to the piston/cylinder unit from the end of the shaft wherethe pressure medium is fed in. However, if the pressure medium supply isto be placed through the motor shaft, the magnetic effect in the motorcould magnetize metal particles in the pressure medium and couldpossibly lead to clogging of the supply lines. In addition, complicatedflexible pressure medium connections would have to be provided in orderto bridge any lateral offsets or axial displacements between the driveunit and the coiler shaft.

Rotary feeds have become known through DE-PS 38 06 931 through which thepressure medium can be conveyed radially into a shaft; these rotaryfeeds have very narrow manufacturing tolerances for an optimumoperation, wherein these very narrow manufacturing tolerances exclude ause in difficult conditions as they prevail in rolling mills. Inaddition, these rotary feeds can only be used up to structural sizeswith a maximum 18 mm diameter at the annular gap. Also for this reason,a use in rolling mill plants, for example, rolling mill coilers, wheresignificantly greater diameters are used, could not take place.

SUMMARY OF THE INVENTION

Therefore, the invention is based on the object of further developing adirectly driven coiler of the generic type in such a way that it can bemoved for spreading and despreading even during the coiling operation.

In accordance with the invention, the direct-drive coiler for windingand/or unwinding rolled strip includes a drum composed of severalsegments which can be moved so as to be spread and which rest withconically-shaped sliding surfaces against a coiling shaft mountedrotatably cantilevered in a coiler housing, and a plunger guided in thecoiler shaft. The plunger is connected through a connecting flange tothe drum segments. An axially extending cylinder is mounted in thecoiler shaft. The cylinder has a piston which is connected to theplunger and which can effect a relative axial displacement between thecoiler shaft and the plunger connected to the segments for producing aspreading movement of the segments. The coiler shaft extends beyond thecylinder with a flanged-on shaft extension which closes the cylinder inthe direction toward the axially arranged, directly driving motor. Arotary feed is provided through which pressure medium can be supplied tothe piston/cylinder unit provided in the coiler shaft. The rotary feedincludes a housing surrounding the coiler shaft and/or the shaftextension, wherein at least one connection each is provided in thehousing as a supply line and a discharge line and a bushing is mountedin the housing for each supply line and discharge line. The inner andouter walls of each bushing are equipped with annular ducts which areconnected to each other through at least one essentially radiallydirected bore. The outer annular ducts extend under the supply anddischarge connections of the housing and discharge provided for thecoiler shaft and/or the haft extension extend under the annular ducts.The rotary feed provides a connection between the piston/cylinder unitand a pressure medium force through which the piston/cylinder unit canbe supplied continuously with pressure medium even when the coiler isdriven so as to rotate for the purposes of winding or unwinding strip.

The rotary feed is to be arranged in such a way that none of thepressure medium lines extends through the shaft of the motor flanged tothe coiler shaft or the shaft extension. Accordingly, it is provided toarrange the rotary feed on the shaft extension. However, it is alsopossible to provide the rotary feed on the coiler shaft itself. By usinga double-acting step piston, the necessary spreading and despreadingforces can be predetermined in accordance with the correspondingpressure of the pressure medium.

Since the rotary feed includes a stationary housing, the externalconnections to the rotary feed can be arranged so as to be stationary.Flexible hoses which are complicated and susceptible to trouble are notnecessary for these connections. The bushings arranged within thehousing can be manufactured significantly more easily than if thehousing would have the corresponding bushing shape. In addition, byseparately providing a housing, the bushings and the sleeve can berealized with different material pairings which ensure that the wear isas little as possible and that they are adapted to each other withrespect to their thermal expansion in such a way that the gaps betweenthe bushings and the sleeves have optimum dimensions even in thedifficult conditions of rolling mills.

The sleeve equipped with the supply ducts can be very easilymanufactured. The use of this sleeve makes possible the use of solidshaft extensions which do not have bores, so that a high stability ofthe shaft extensions is ensured.

The pressure medium emerging between the sleeve and the bushings,through which the bushing rests on an oil film on the sleeve, isdischarged through leakage oil lines to a tank. The piston/cylinder unitis also provided with leakage oil lines which end in the oil tank. Theleakage oil lines of the piston/cylinder unit only conducts oil if sealsof the piston/cylinder unit are detected. In that case, leakage oilindicators can be provided which indicate the defect of the seals.

In order to ensure that the oil between the sleeve and the bushings isnot interrupted during the coiling operation, a predetermined oilpressure level must always be maintained on the pressure medium lines.The pressure medium line “spreading” is then under sufficient pressure,so that a stable oil film is ensured. The pressure medium line“despreading” could theoretically be without pressure during the coilingoperation, which, however, would lead to damage of the rotary feed ifthe oil pressure level were not also maintained on the pressure mediumline “despreading”.

However, it is also possible to provide additional annular ducts andradial bores in the bushings in order to maintain through the ducts andbores statically an oil film between the sleeve and the correspondingbushing. In that case, the pressure medium lines “despreading” couldalso remain without pressure during the operation. The oil film has thepurpose of absorbing the great weight of the bushings and anyacceleration forces which occur at the rolling mill coilers as aconsequence of vibrations. A significant advantage of the static oilfilm results from the elastic expansion of the sealing gap. As a result,defects with respect to shape, for example, deviations from the circularshape, which could occur as a result of the mechanical processing and achange of the natural stress condition under pressure and temperature,are compensated.

The outer surface of the sleeve and/or the inner surface of the bushingshave ceramic coatings to ensure a longer service life of the sleeve andof the bushings. The resilient support of the bushings in the housing,for example, through O-rings, is advantageous for compensating forsymmetric deviations which may occur when manufacturing the individualstructural components. The bushings are centered through the oil film onthe sleeve and are provided by the O-rings with the possibility ofadjusting themselves to the position of the sleeves.

BRIEF DESCRIPTION OF THE DRAWING

The invention will be explained in more detail with the aid of adrawing. In the drawing:

FIG. 1 shows a coiler according to the invention;

FIG. 2 is a partial sectional view corresponding to FIG. 1;

FIG. 3 shows a piston/cylinder unit according to the invention;

FIG. 4 shows a rotary feed according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 shows a coiler 1 composed of a drum 2 onto which is wound a coil3, a coiler shaft 4, a shaft extension 5, a shaft coupling 6 and a motor7. A rotary feed 8 is arranged on the shaft extension 5. The coiler 1 isprovided with a push member 10 arranged on a guide 9; the push member 10has the purpose of pushing the coils 3 from the drum 2.

FIG. 2 shows the drum 2 in a partially spread and partially despreadposition. The drum segments 11 are displaceable on the coiler shaft 4through a plunger 12 and a connecting flange 13. The plunger 12 can bedriven by a piston/cylinder unit 14 which is connected through pressuremedium lines 15, 15′ to the rotary feed 8.

FIG. 3 shows the piston 16 and the cylinder 17 of the piston/cylinderunit 14 integrated in the coiler shaft 4. The cylinder 17 is heldaxially by the shaft extension 5. The piston 16 is connected throughscrews 18 to the plunger 12. The pressure medium lines 15, 15′, shownarranged one behind the other in FIG. 3, end in the cylinder spaces 19,20. The piston 16 is sealed in the cylinder 17 through sealing rings 21.Leakage oil lines 22 have the purpose of collecting any emerging leakageoil quantities and to discharge them to an oil tank, not shown. If oilis conducted in the leakage oil lines 22, this is a sign that thesealing rings 21 are damaged.

FIG. 4 shows the shaft extension 5 on which the rotary feed 8 isarranged. The rotary feed 8 is composed of a housing 23 in whichbushings 24, 25 are mounted. The bushings 24, 25 are mounted on a sleeve26 which surrounds the shaft extension 5.

Provided on the housing 23 is a connection 27 for the pressure mediumfor the spreading procedure of the drum 2 as well as a connection 28 forthe pressure medium for despreading the drum 2. In the area in which theconnections 27, 28 overlap the bushings 24, 25, the bushings 24, 25 haveannular ducts 29 which are connected to annular ducts 31 through thedischarge bores 30. The annular ducts 31 are located opposite dischargebores 32 in the sleeves 36. The discharge bores 32 end in the pressuremedium lines 15, 15′.

The bushings 24 and 25 are mounted in the housing 23 through O-rings 33.During operation, an oil film on which the bushing 24 floats is formedbetween the bushings 24 and sleeve 26. The oil emerging between thebushing 24 and the sleeve 26 is collected by a leakage oil line and issupplied to the oil tank, not shown.

The annular duct 31 of the bushing 25, which is located opposite theconnection 28 for despreading, may be without pressure during the normalcoiling operation. If a bushing corresponding to the bushing 24 were tobe used for the bushing 25, a certain pressure would have to prevailduring the coiling operation also in the despreading line, so that thelubrication between the bushing and the sleeve 26 is ensured.

However, the bushing 25 shown in FIG. 4 has additional annular ducts 34,35; 34′, 35′ and radial bores 36; 36′ through which a pressure mediumfor maintaining the sliding film is conducted continuously into the gapbetween the bushing 25 and the sleeve 26. The connection 37 has thepurpose of conducting the lubricant to the bushing 25 in order to ensurein this manner the hydrostatic support of the bushing 25 on the sleeve26 without the requirement that pressurized medium must be present atthe connection 28. Of course, a corresponding hydrostatic configurationcould also be provided for the bushing 24 or any additional bushingswhich are not shown.

List of Reference Numerals

1 Coiler

2 Drum

3 Coil

4 Coiler Shaft

5 Shaft Extension

6 Shaft Coupling

7 Motor

8 Rotary Feed

9 Guide

10 Push Member

11 Drum Segments

12 Plunger

13 Connecting Flange

14 Piston/Cylinder Unit

15 Pressure Medium Line

16 Piston

17 Cylinder

18 Screw

19 Cylinder Space

20 Cylinder Space

21 Sealing Ring

22 Leakage Coil Line

23 Housing

24 Bushing

25 Bushing

26 Sleeve

27 Connection

28 Connection

29 Annular Duct

30 Radial Bore

31 Annular Duct

32 Discharge Bore

33 O-Ring

34 Annular Duct

35 Annular Duct

36 Radial Bore

37 Connection

What is claimed is:
 1. Direct-drive coiler for winding and/or unwindingrolled strip with a drum composed of several segments which can be movedso as to be spread and which rest with conically-shaped sliding surfacesagainst a coiling shaft mounted rotatably cantilevered in a coilerhousing, with a plunger guided in the coiler shaft, wherein the plungeris connected through a connecting flange to the drum segments, whereinan axially extending cylinder (17) is mounted in the coiler shaft (4),wherein the cylinder (17) has a piston (16) which is connected to theplunger (12) and can effect a relative axial displacement between thecoiler shaft and the plunger connected to the segments for producing aspreading movement of the segments, wherein the coiler shaft (4) extendsbeyond the cylinder (17) with a flanged-on shaft extension (5) whichcloses the cylinder (17) in the direction toward the axially arranged,directly driving motor (7), and a rotary feed (8) is provided throughwhich pressure medium can be supplied to the piston/cylinder unit (14)provided in the coiler shaft (4), characterized in that the rotary feed(8) includes a housing (23) surrounding the coiler shaft (4) and/or theshaft extension (5), wherein at least one connection (27, 28) each isprovided in the housing (23) as a supply line and a discharge line and abushing (24, 25) is mounted in the housing (23) for each supply line anddischarge line, wherein the inner and outer walls of each bushing areequipped with annular ducts (29, 31) which are connected to each otherthrough at least one essentially radially directed bore (30), whereinthe outer annular ducts (29) extend under the supply and dischargeconnections (27, 28) of the housing (23) and discharge bores (32)provided for the coiler shaft (4) and/or the shaft extension (5) extendunder the annular ducts (31).
 2. Direct-drive coiler according to claim1, wherein the discharge bores (32) are provided in a sleeve (26)surrounding the coiler shaft (4) and/or the shaft extension (5), whereinthe sleeve (26) has pressure medium lines (15, 15′) to thepiston/cylinder unit (14).
 3. Direct-drive coiler according to claim 2,wherein at least the bushing (25) has additional annular ducts (34, 35;34′, 35′) and radial bores (36; 36′) connecting the additional annularducts, wherein pressure medium can be supplied to the radial bores foreffecting the lubrication between the sleeve (26) and the bushing (25).4. Direct-drive coiler according to claim 2, wherein the outer surfaceof the sleeve (26) and/or the inner surfaces of the bushings (24, 25)are coated with ceramic material.
 5. Direct-drive coiler according toclaim 1, wherein the piston/cylinder unit (14) and the rotary feeds (8)have collection spaces for leakage oil which can be supplied to an oiltank through leakage oil lines (22).
 6. Direct-drive coiler according toclaim 1, wherein during the coiler operation at least one predeterminedpressure level is maintained on the pressure medium lines (15, 15′). 7.Direct-drive coiler according to claim 1, wherein the bushings (24, 25)are mounted resiliently in the housing (23).